This invention relates to a suspended roof construction for industrial furnaces, and more particularly to a refractory roof having a generally flat planar cold face surface which permits easy cleaning. The roof construction of this invention may be preassembled exterior to the furnace in panels which may be lowered between spaced support structures and extended beneath the structures after installation. The roof construction provides easy replacement of entire sections of the suspended roof.
The suspension of refractory bricks in the roof construction of high temperature industrial furnaces is disclosed in U.S. Pat. Nos. 3,824,936 and 4,073,243 which are incorporated herein by reference in their entirety. While the constructions shown in these patents have been generally successful in commercial practice, they are not as easy to clean as desired. Prior art suspended roof designs have not provided roof structures as easy to construct or as easy to repair as desired.
U.S. Pat. No. 3,824,936 describes a roof construction wherein a plurality of basic refractory brick assembly units depend downwardly from hangers which are suspended from a suitable frame. Each assembly unit has a carrier brick having a reduced head portion and a body portion. The reduced head portion is provided with a hole through which an elongated rod extends holding adjacent carrier bricks. The elongated rod is hung on the hangers which extend between the reduced head portions of adjacent carrier bricks. Two filler bricks may be supported by each carrier brick. This construction results in recesses and unevenness on the top surface, or cold face, which is difficult to clean, requires removal of relatively large sections for repair, and requires a horizontal hanger rod through each carrier brick which in turn supports two filler bricks in addition to vertical hanger rods.
In the roof construction shown in U.S. Pat. No. 4,073,243, refractory bricks are suspended from hanger rods which are secured in recesses in one side of the bricks. One hanger rod is required for each pair of bricks, which is undesirable because each rod is an obstacle to cleaning.
There is a need for a suspended roof construction for high temperature furnaces which may be easily constructed and repaired and provides a substantially flat, unobstructed, easy cleaning cold surface.
It is desirable to assemble refractory bricks in panel units before installation in the furnace. When replacement of a section of the furnace roof is required, the panel may be removed and repaired away from the furnace and replaced. It is desirable to remove and replace the panels from the cold side of the roof, so that the furnace need not be completely shut down to effect the repairs.
The furnace roof panels are generally suspended from support means which are secured to a support frame, such as I-beams. The roof panels must be shorter than the space between adjacent members of the support frame so that they may be lowered between the frame members for installation, and raised between the frame members for removal and repair. However, such roof panels do not fill the area of the roof construction below the support frame and the areas between adjacent roof panels must be filled with bricks which must be suspended from above.
Accordingly, an object of the present invention is to provide an improved refractory suspended roof construction for high temperature industrial furnaces which affords easier construction and reduced maintenance as compared to present suspended refractory roofs.
Another object of this invention is to provide a suspended roof construction for high temperature furnaces having a substantially planar, continuous cold face surface which permits the surface to be easily cleaned.
Still another object of this invention is to provide a suspended roof construction for industrial furnaces which is easy to repair.
Yet another object of this invention is to provide a suspended roof construction for industrial furnaces which has multiple roof panels, each of which may be easily lowered or raised between adjacent support frame members and provide means for suspending bricks in the spaces between adjacent roof panels.
It is another object of this invention to provide roof panels for suspended refractory roof construction which have telescoping extension hanger supports for suspending bricks in spaces between adjacent roof panels.